Automatic snatch block



Jun 24, 1930.

c. ROBERTSQN AUTOMATIC SNATGH BLOCK Filed Oct. 12, 1928 5 Sheets-Sheet 2 Chariwfiaberljan.

INVENTQR o v BY ATTORNEY June 24, 1930. c. ROBERTSON AUTOMATIC SNATCH BLOCK Filed Oct. 12, 1928 3 Sheets-Sheet 3 a w; I

ATTOR NEY Patented June 24, 193% "PATENT orrlce CHARLES ROBERTSON, OF 1 SEATTLE, WASHINGTON AUTOMATIC. SNATCH BLOCK This invent-ion relates to new and useful improvements in connections in the nature of block, fall hooks and sheaves, to prevent displacement of the leads therefor.

An object of the invention comprehends a closure for the open end of the sheave and normally retained in a closed position by the attaching means therefor.

An additional object of the invention resides in the provision of auxiliary mountings for the sheaves whereby the latter may be retained in operative position in the event the block pin should break.

More specifically stated the closure is 6 adapted for selective connection with a portion of the sheave housing to prevent distortion of same when subjected to excessive draft.

\Vith the above and other objects in view, the invention further consists in the following novel features and details of construcsion, to be hereinafter more fully de scribed, illustrated in the accompanying drawings and pointed out in the appended claims.

In the drawings Figure 1 is an elevation of my improved type of sheave illustrating the relative arrangement ofthe assembled parts in dotted lines. a

Figure 2 is a longitudinal sectional view taken on line 22 of Figure 1 withthe closure member in locked position.

Figure 3 is a longitudinal sectional view taken on line of Figure 7 with the closure member arran ed in open position.

Figure d is a longitudinal sectional view taken on line 1% of Figure 1 through the sheave per se and bearing plate therefor.

Figure is a sectional view taken on line 5-5 of Figure 3.

Figure (Sis a perspective view of the closure member per'se.

Figure 7 is a fragmentary side elevationof the sheave body with the sheave removed Application filed October 12, 1928. Serial No. 312,182.

and furthermore illustrating the relative arrangement of the open end of the sheave body and the closuremember.

Figure 8 is-an elevation of a modified form of my invention partly broken away to illustrate the "constructionthereof.

Figure9 is a fragmentary detail sectional viewof additional modification of-the invention.

Referring to the drawings in detail, wherein like characters of reference denote corresponding parts, the reference character 10 indicates generally the body of a sheave housing of U-shape and preferably channel formprovided with an extension 11 upon one end which is upwarly' and iiiwardly piojecte'd therefrom. A sleeve 12, carried upon the extremity of the extension 11, is provided with communicating bores 13 and 1+lrespectively. The shank *15 of an attachinghook 16,slidably mounted within the bore 14 of the sleeve 12, carries a compression spring 17 upon that portion projected within thebore 13 and sprung at its ends against the shoulder portion as defined between the shank and the hook properand the shoulder formed between the counter bores in the sleeve 12.

A'spring 17 is adapted to normally retain and induce an enlarged head 18 within a seat 19 in the opposite end of the sleeve and having communication with oneend of the bore 14L.

A closure member 20, having a bearing portion 21 upon one end and journaled within an appropriate portion of the sleeve 12 remotely disposed from the head 18 of the shank l5 and the seat 19 therefor, is provided with guide flanges 22 upon the sides-thereof andengageable'with the channel walls of the sheave body. The closureis furthermore provided with an elongated slot 23 adapted to accommodate the head 18 upon the shank 15 whereas a communicating slot 2% i of the configuration shown in Figure 6 of the drawings is adapted to receive the shank proper. The compression spring 17 will "force the adjacent side of the head 18 to engage the marginal.

. edges of the apertured portions of the closure to normally retain the opposite end of said closure in the Figure 2 position. Fingers and 26, carried upon the free end of the closure member 20 and the adjacent end of the sheave body, are adapted for interfitting engagement, substantially as illustrated in Figures 1, 2 and 7 of the drawings. A pin 27, horizontally disposed within the lingers 25, is adapted to dispose the exposed portions thereof between the fingers 25 within pockets 28 provided within the inner sides of the fingers 26, substantially as illustrated in Figures 2 and 3 of the drawings.

The connection established between the shorter end of the sheave body and the particular end of the closure member will prevent distortion of the sheave body when the latter is subjected to excessive draft.

A sheave or pulley 29, journaled upon a block pin 30, is adapted for rotation between the long and short ends of the sheave body in the manner illustrated in Figure 2 of the drawings. lhe pin 30 is adapted for reception at one end within the opening 31 in the longer end of the sheave body Whereas a shoulder 32, formed adjacent its opposite end is passed through an opening 33 in a disk member 34. An annular flange 35,1'ightangularly disposed, upon the disk 34, is

adapted for connection with the shorter end of the sheave body and within an opening 36 therefor through the instrumentality of a bayonet slot connection. Sleeves 37 and 38 respectively, inwardly projecting from the inner side walls of the longer end of the sheave body and disk 34 eircumferentially of the openings 31 and 33, also accommodate the ends of the pulley or sheave 29. In the event the block pin 30 should break, the sleeves 37 and 38 would. retain the pulley or sheave 29 in position for use and provide a mounting therefor, whereby the cable member, not shown, would be guided thereover.

The Figure 3 position of the closure 20 will permit passage of the looped end of a cable member for connection with the pulley or sheave.

In Figure S-oi the drawings, I have illustrated a modification of the invention, and which departs from the form of my invention as previously described and illustrated in the substitution of a hook-like body 39 in place of the conventional sheave body 10. The closure member is similar in construction to the closure member 20 and in this instance is adapted for detachable connection with the free end of the hook. Furthermore, a ring 16' is employed instead oi the hook 16. Such construction is merely a matter of choice and does not pretend to depart from the spirit of the invention as disclosed in the preferred embodiment of my invention.

Figure 9 is illustrative of an additional modification oi the invention, embodying a rearrangement of closure. Instead of disposing the closure within the enclosure defined by the sheave body, the same is arranged upon the outside whereby allowance is made for the whipping action of cables upon the sheave.

The invention is susceptible of various changes in its form, proportions and minor details of construction, and the right is herein reserved to make such changes as properly fall Within the scope of the appended claims.

Having thus described the invention, what is claimed is 1. A snatch block comprising a body portion open at one end, a connecting element carried upon one end of the body, a spring included upon the attaching portion of the connecting element being adapted to normally tension same to occupy an extended position, and a closure member mounted upon the body and operable in conjunction wvith the attaching portion of the connecting element for detachable locking engagement with the open end of the body.

2. A snatch block comprising a body portion open at one end, a connecting element carried upon one end of the body, a spring included upon the attaching portion of the connecting element being adapted to normally tension same to occupy an extended position, a closure member mounted upon the body and operable in conjunction with the attaching portion of the connecting element for detachable locking engagement with the open end of the body, and a sheave journaled within the body.

3. A snatch block comprising a body portion having long and short ends, a sleeve carried upon the longer end of the body, an attaching element having a shank projected within the bore of the sleeve, a head included upon the shank, a compression spring encircling the shank within the bore of the sleeve to normally retain the head in a desired position, a closure member pivotally mounted within the sleeve and operable by said head, and a pin passed through the free end of the closure being adapted for detachable connection with the shorter end of the body.

4. A snatch block comprising a body portion having long and short ends, a sleeve carried upon the longer end of the body, an attaching element having a shank proj ected within the bore of the sleeve, a head included upon the shank, a compression spring encircling the shank within the bore of the sleeve to normally retain the head in a ture.

CHARLES ROBERTSON. 

